Feeling PROUDLY South African, hence the insertion of our "beautiful" flag onto OSMOSIS title bar.
• wiki.answers.com claims that the colours stand for the following:

Red: bloodshed of activists
White: white population
Blue: skies or the ocean, since SA is bordered by 2 oceans
Yellow: minerals
Green: agriculture and land
Black: the non-white population or Mr Mandela, the ex-head of SA.

The South African government's official website stresses the following:

"Individual colours, or colour combinations represent different meanings for different people and therefore no universal symbolism should be attached to any of the colours."

WHAT DO YOU THINK THE COLOURS STAND FOR?